Former President Bill Clinton, second from left, stands with fellow democrats State Rep. Pete Gallego, D-Alpine, left, San Antonio Mayor Julian Castro, and U.S. congressional hopeful Joaquin Castro, right, during a campaign rally, Thursday, Oct. 25, 2012, in San Antonio. (AP Photo/Eric Gay) less

Former President Bill Clinton, second from left, stands with fellow democrats State Rep. Pete Gallego, D-Alpine, left, San Antonio Mayor Julian Castro, and U.S. congressional hopeful Joaquin Castro, right, ... more

Photo: Associated Press

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The candidate listen to results after 10:30 during the election night watch party for State Representative Pete Gallego, D-Alpine, who is challenging U.S. Representative Francisco Canseco for his seat in the U.S. House District 23 on November 6, 2012. less

The candidate listen to results after 10:30 during the election night watch party for State Representative Pete Gallego, D-Alpine, who is challenging U.S. Representative Francisco Canseco for his seat in the ... more

Photo: San Antonio Express-News

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In this Sept. 25, 2012 file photo, State Rep. Pete Gallego, D-Alpine, speaks during a Spanish-language debate against Republican U.S. Rep. Francisco "Quico" Canseco at Palo Alto College in San Antonio, Texas. (AP Photo/The San Antonio Express-News, John Albright, File) RUMBO DE SAN ANTONIO OUT; NO SALES less

In this Sept. 25, 2012 file photo, State Rep. Pete Gallego, D-Alpine, speaks during a Spanish-language debate against Republican U.S. Rep. Francisco "Quico" Canseco at Palo Alto College in San Antonio, Texas. ... more

Photo: Associated Press

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Charlie Gonzalez congratulates Pete Gallego at the election night watch party for State Representative Pete Gallego, D-Alpine, who is challenging U.S. Representative Francisco Canseco for his seat in the U.S. House District 23 on November 6, 2012. less

Charlie Gonzalez congratulates Pete Gallego at the election night watch party for State Representative Pete Gallego, D-Alpine, who is challenging U.S. Representative Francisco Canseco for his seat in the U.S. ... more

Rep. Pete Gallego, D-Alpine, is asking the state comptroller to update a study on the fiscal impact of Texas’ population of undocumented immigrants.

The request — by way of a letter sent to Comptroller Susan Combs late Tuesday — comes on the heels of an overwhelming U.S. Senate vote to invoke cloture and proceed with debate on the comprehensive immigration reform bill authored by the upper chamber’s “Gang of Eight.”

The last time such a state study was performed was in 2006, by then-Comptroller Carol Keeton Strayhorn. The results showed that if the estimated 1.4 million undocumented immigrants who lived in the state in 2005 were sent home, Texas would have lost about $17.7 billion in gross domestic product that year.

The population also produced more in-state revenue that year — $1.58 billion — than the $1.16 billion it cost in state services. Local governments, however, lost about $1.44 billion in combined health care and law enforcement costs that were not reimbursed by the state, according to the study.

Combs, whose duties end in January 2015, announced this month that she would not seek another term or run for another office. Her office has said over the years that it had no intention of updating the study, which was authored by a different administration. During the regular session of the 83rd Legislature, however, some bipartisan advocates for immigration reform suggested it was time to update the analysis in order to add more context to an issue deeply shrouded in emotion.

Gallego said renewing the study should be an easy enough task because the framework is in place and the data simply needs to be updated. The results could prove invaluable during the current debate, he added.

“Your report would be vital to the 38 Texas members of Congress, and to other elected officials and decision-makers as they grapple with immigration reform,” he said. “The study might also assist in shaping legislation related to immigration at the state and local levels.”

During the 83rd Legislature’s regular session that ended last month, state Rep. Rafael Anchia, D-Dallas, co-authored a concurrent resolution urging Congress to “swiftly enact and fund comprehensive immigration reform that creates a road map to citizenship.” He included language from the 2006 study in the resolution. On Tuesday, he said he welcomed the idea of an update to help give Texans a clearer picture of what is being debated.

“I suspect it will show an even greater economic impact than the 2006 study,” he said. “The numbers are what the numbers are. I would expect the comptroller to play it straight down the fairway.”

Gallego served in the Texas House from 1991 until his election to Congress last year. In 2011, he chaired the House Committee on Criminal Jurisprudence and was also a member of the State Affairs Committee, which heard testimony on dozens of immigration enforcement bills filed during the 82nd Legislature. In his letter, he referenced a study by the Immigration Policy Center that reflected the net-positive impact undocumented immigrants in Texas have on the state’s coffers.

“If all unauthorized immigrants were removed from Texas, the state would lose $69.3 billion in economic activity, $30.8 billion in gross state product, and approximately 403,174 jobs, even accounting for adequate market adjustment time,” Gallego said, quoting the IPC. “An updated study from the Texas Comptroller’s office would shed light on the true impact to our state by unauthorized immigrants.”

Gallego is asking Combs to rely on the same framework Strayhorn used — which the former comptroller suggested may have actually underestimated the impact.

“This is a result of the difficulty in calculating the number of undocumented immigrants in the state and the number who access state paid services,” Strayhorn wrote in the 2005 study. “It is difficult to count a population that does not want to be counted, particularly when the law allows them access to many government services without regard to citizenship, such as those delivered by public hospitals and public schools.”